Final answer:
The coordinates of point B are (-1, 11).
Step-by-step explanation:
To find the coordinates of point B, we can use the midpoint formula. The midpoint formula states that the coordinates of the midpoint of a line segment are the average of the coordinates of the endpoints. We are given that point M is the midpoint of vector (AB), and the coordinates of M are (2,8). The coordinates of A are (10,12).
Let's use the midpoint formula:
Midpoint = ((x1 + x2)/2, (y1 + y2)/2)
Substituting the given values, we have:
(2,8) = ((10 + x2)/2, (12 + y2)/2)
Simplifying the equation, we get:
(2,8) = (5 + x2)/2, (6 + y2)/2)
Multiplying both sides of the equation by 2, we have:
(4, 16) = (5 + x2, 6 + y2)
Subtracting 5 from both sides of the equation, we get:
(4, 16) - (5, 5) = (x2, y2)
Simplifying the equation, we have:
B = (-1, 11)